There are considerable array of tools available for the modern gardeners. For example, shears are used for pruning or cutting “light” vegetation such as grass or leaves or twigs etc. Hedge trimmers and chain saws are used for cutting “heavy” vegetation such as trees.
A traditional chain saw comprises a cutting head. The cutting head comprises a flexible chain and a guide bar for supporting the flexible chain. The flexible chain is driven by a motor received in a motor housing and runs along the peripheral of the guide bar. A traditional chain saw further comprises a main handle positioned behind the cutting head, an assistant handle positioned between the cutting head and the main handle. During cutting, the cutting head is driven by the motor and the flexible chain runs along the peripheral of the guide bar, the guide bar does not move with respect to the motor housing. In operation, one hand of the operator grasps the main handle, and the other hand of the operator grasps the assistant handle, the operator should press the saw toward the cutting direction to ensure smoothly cutting. When the cutting direction is from up to down, operating of the traditional chain saw will be not so hard for the gravity of the saw. But if the cutting is from down to up or from left side to right side, operating of the traditional saw will be very hard and need great effort.
U.S. Published Patent Application No. 2005/0022388A1 discloses a vegetation pruning device. The vegetation pruning device comprises a cutting head. The cutting head comprises a flexible chain and a guide bar for supporting the flexible chain. The flexible chain is driven by a motor and running around the guide bar. The vegetation pruning device further comprises a pair of pivotally coupled arms. The pivotally coupled arms rotate about a fixed axis. The cutting head is connected to one of the arm and can pivot together with the arm around the fixed axis relative to the other arm. Each arm is connected with a handle portion for the operator to grip. In use, the operator moves the handle portions close to each other, the arms will move close correspondingly, thereby the cutting work can be proceed. But this kind of vegetation pruning device makes that in some instance the operation is not so comfortable. For example, when you need to cut branch of high trees, it's hard to make such a cutting with this kind of vegetation pruning device. In other instance, such as cutting wood placed on the floor, the operator should bow, if the operating last long, it is very easy to feel exhaust.